Siamp fill valve ... yeah, again

[TomCrap]

G'day all. New to this site (not a plumber) but with a familiar problem, albeit with a twist. Wickes toilet in a box with Siamp internals fitted 5 years ago and has been fine until the last week ... slow to fill, so replaced split diaphragm (well documented on this site), which cured spraying from around connection but now water spurts out of top of fill valve through central circular hole in cap! The washer beneath the cap looks OK but has nothing in its own central hole. Found a plastic plug in bottom of tank but when fitted in hole (and I don't know if it should go there) it just gets blown out by water pressure. Float works fine and shuts water off correctly. Have put old washer back in for the time being as that scenario (slow fill) was preferable to water dripping from lid! I cannot work out how this contraption functions and just wondered if there are any ideas out there before I resort to replacing the whole valve assembly.

 

[Agile]

Bit difficult to follow your explanation. A photo would help.

You can probably slow the water down by adjustment of the ISO valve.

The cap you found was probably from the siphon and adjusts the flush volume.

Tony

 

[TomCrap]

Thanks for prompt reply .... difficult to explain without photos, as you suggest, and a bit of a long shot really; just wondered if it would ring any bells with anyone. No time at the mo to investigate knack of getting photos on - may get chance over the weekend.

 

[Richardthe3rd]

G'day all. New to this site (not a plumber) but with a familiar problem, albeit with a twist. Wickes toilet in a box with Siamp internals fitted 5 years ago and has been fine until the last week ... slow to fill, so replaced split diaphragm (well documented on this site), which cured spraying from around connection but now water spurts out of top of fill valve through central circular hole in cap! The washer beneath the cap looks OK but has nothing in its own central hole. Found a plastic plug in bottom of tank but when fitted in hole (and I don't know if it should go there) it just gets blown out by water pressure. Float works fine and shuts water off correctly. Have put old washer back in for the time being as that scenario (slow fill) was preferable to water dripping from lid! I cannot work out how this contraption functions and just wondered if there are any ideas out there before I resort to replacing the whole valve assembly.

Most of these fill valves are equilibrium type valves. These shut off by equal pressure on both sides of the main washer stopping the water flow.

Many DaftyDIYers & Plumbers will just replace them, but most are very easy to re-washer. Just have the correct washers & it's a far easier job to repair the valve
HTH